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Design and Control of a Bionic Inspection Robot for Suspension Bridge Main Cables
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作者 Shengkai Liu Chao Wang +1 位作者 Xiaoqiang Yuan Ning Ding 《Journal of Bionic Engineering》 2026年第1期159-174,共16页
The main cable is the primary load-bearing component of a suspension bridge,continuously exposed to harsh environmental conditions,such as wind and rain,throughout the year.These adverse conditions contribute to varyi... The main cable is the primary load-bearing component of a suspension bridge,continuously exposed to harsh environmental conditions,such as wind and rain,throughout the year.These adverse conditions contribute to varying degrees of degradation and damage to the main cable,necessitating regular inspections to prevent catastrophic failures.Traditional manual inspection methods not only suffer from low efficiency but also pose significant safety risks to personnel.To address these challenges and ensure the safe and effective inspection of suspension bridge main cables,this study introduces a novel cooperative climbing robot,designated as Main Cable Robot Version II(CCRobot-M-II),inspired by the locomotion of the inchworm.The robot employs an alternating opening and closing mechanism of four gripper sets,mimicking the inchworm's movement to achieve efficient crawling along the suspension bridge handrails.This paper provides a comprehensive analysis of the structural design,key components,and motion mechanisms of CCRobot-M-II.A detailed force analysis of the robot's crawling process is also presented,followed by the design of the control system and the development of an efficient motion control algorithm.Laboratory experiments demonstrate that the robot achieves a positional error of 00.64%during crawling,with a maximum average crawling speed of 7.6 m/min.Furthermore,the biomimetic design enables the robot to overcome obstacles up to 30 mm in height and possess the capability to handle suspension bridge cables with spans ranging from 740 to 1100 mm.Finally,CCRobot-M-II successfully conducted an inspection of the main cable on a suspension bridge,marking the world's first successful deployment of a climbing robot for main cable inspection on a suspension bridge. 展开更多
关键词 Bionic design Suspension bridge main cable inspection Climbing robot Motion control
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Photoacoustic imaging and main lobe width analysis for enhancing microwave ablation monitoring of liver tissue
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作者 Min Wan Yameng Zhang +4 位作者 Shihao Tang Zhiyu Qian Fan Gao Yamin Yang Weitao Li 《Journal of Innovative Optical Health Sciences》 2026年第2期129-140,共12页
Microwave ablation(MWA)is a minimally invasive technique for treating hepatic tumors,necessitating precise monitoring to ensure treatment efficacy and minimize damage to surrounding tissues.This study explores the pot... Microwave ablation(MWA)is a minimally invasive technique for treating hepatic tumors,necessitating precise monitoring to ensure treatment efficacy and minimize damage to surrounding tissues.This study explores the potential of photoacoustic imaging(PAI)in monitoring MWA by examining ex vivo porcine liver tissues.In this study,a comprehensive analysis of photoacoustic signals was performed to compare the main lobe width(MLW)between ablated and normal regions in porcine liver tissue.Histological staining with succinate dehydrogenase(SDH)and shear wave elastography(SWE)were employed to validate the changes in tissue elasticity after ablation.The analysis demonstrated a notable reduction in the MLW of the average A-lines in ablated tissues compared to nonablated regions(p<0.01).This reduction,attributed to increased tissue density and enhanced elasticity,indicates accelerated sound propagation in thermally ablated areas,which then serves as a critical parameter for mapping tissue characteristics.The reconstruction of the MLW distribution successfully delineated the ablated regions,and was consistent with the results of SDH staining and SWE.In addition,MLW-based imaging exhibited higher spatial resolution compared to SWE.Incorporating MLW analysis into PAI may be a promising strategy to improve the accuracy and effectiveness of MWA monitoring in clinical settings. 展开更多
关键词 Photoacoustic imaging main lobe width microwave ablation tissue density shear wave elastography
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Main factors controlling unconventional gas enrichment and high production in the first member of Permian Maokou Formation,southeastern Sichuan Basin,SW China 被引量:2
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作者 HE Guisong SUN Bin +4 位作者 GAO Yuqiao ZHANG Peixian ZHANG Zhiping CAI Xiao XIA Wei 《Petroleum Exploration and Development》 2025年第2期408-421,共14页
Based on the data of drilling,logging,experiment and gas testing in the Nanchuan area,southeastern Sichuan Basin,the hydrocarbon generation potential,gas genesis,occurrence state,migration,preservation conditions,pore... Based on the data of drilling,logging,experiment and gas testing in the Nanchuan area,southeastern Sichuan Basin,the hydrocarbon generation potential,gas genesis,occurrence state,migration,preservation conditions,pore and fracture features and accumulation evolution of the first member of Permian Maokou Formation(Mao 1 Member)are systematically studied,and the main controlling factors of unconventional gas enrichment and high production in marlstone assemblage of Mao 1 Member are discussed.(1)The enrichment and high yield of unconventional natural gas in the Mao 1 Member are controlled by three factors:carbon-rich fabric controlling hydrocarbon generation potential,good preservation controlling enrichment,and natural fracture controlling production.(2)The carbonate rocks of Mao 1 Member with carbon rich fabric have significant gas potential,exhibiting characteristics of self-generation and self-storage,which lays the material foundation for natural gas accumulation.(3)The occurrence state of natural gas is mainly free gas,which is prone to lateral migration,and good storage conditions are the key to natural gas enrichment.Positive structure is more conducive to natural gas accumulation,and a good compartment is created jointly by the self-sealing property of the Mao 1 Member and its top and bottom sealing property in monoclinal area,which is favorable for gas accumulation by retention.(4)Natural fractures are the main reservoir space and flow channel,and the more developed natural fractures are,the more conducive to the formation of high-quality porous-fractured reservoirs and the accumulation of natural gas,which is the core of controlling production.(5)The accumulation model of unconventional natural gas is proposed as“self-generation and self-storage,preservation controlling richness,and fractures controlling production”.(6)Identifying fracture development areas with good preservation conditions is the key to successful exploration,and implementing horizontal well staged acidizing and fracturing is an important means to increase production and efficiency.The study results are of referential significance for further understanding the natural gas enrichment in the Mao 1 Member and guiding the efficient exploration and development of new types of unconventional natural gas. 展开更多
关键词 Sichuan Basin PERMIAN Maokou Formation unconventional natural gas main controlling factors of enrichment and high production accumulation model carbonate rock southeastern Sichuan Basin
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Enhanced Ion Sampling Techniques for In-situ Neutral Gas and Low-energy Ions Exploration of Main-belt Comet
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作者 WANG Xinyue ZHANG Aibing +4 位作者 SU Bin DU Dan KONG Linggao TIAN Zheng ZHENG Xiangzhi 《空间科学学报》 北大核心 2025年第3期749-760,共12页
One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific object... One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water. 展开更多
关键词 neutral gas low energy ions sampling techniques ion sampling techniques investigate space environment main belt comet gas ion analyzer gia situ measurement
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Hydraulic Sliding Formwork Construction Technology for Main Pier Columns of Highway Bridges
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作者 Guangpu Dong Liang Wang 《Journal of World Architecture》 2025年第1期1-6,共6页
Aiming at the problems of difficulty in balancing construction efficiency and quality,as well as the high safety risks of working at heights during the construction of main piers for highway bridges,this study takes a... Aiming at the problems of difficulty in balancing construction efficiency and quality,as well as the high safety risks of working at heights during the construction of main piers for highway bridges,this study takes a specific bridge project as an example to introduce the technology of hydraulically sliding formwork for the construction of main piers of highway bridges.An in-depth analysis of the project’s construction process found that this technology can effectively improve construction efficiency,ensure the quality of concrete pouring,and significantly reduce the potential safety hazards of working at heights.It provides a reliable technical solution for constructing the main piers of highway bridges and has important reference significance for similar projects. 展开更多
关键词 Highway bridges main piers Hydraulic pressure SLIDING FORMWORK
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Research on the Selection and Layout Scheme of Main Transformers in the Primary Electrical Design of New Energy Step-Up Stations
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作者 Yuekai Liao 《Journal of Electronic Research and Application》 2025年第4期254-260,共7页
This paper focuses on the research of the main transformer selection and layout scheme for new energy step-up substations.From the perspective of engineering design,it analyzes the principles of main transformer selec... This paper focuses on the research of the main transformer selection and layout scheme for new energy step-up substations.From the perspective of engineering design,it analyzes the principles of main transformer selection,key parameters,and their matching with the characteristics of new energy.It also explores the layout methods and optimization strategies.Combined with typical case studies,optimization suggestions are proposed for the design of main transformers in new energy step-up substations.The research shows that rational main transformer selection and scientific layout schemes can better adapt to the characteristics of new energy projects while effectively improving land use efficiency and economic viability.This study can provide technical experience support for the design of new energy projects. 展开更多
关键词 New energy step-up substation Engineering design main transformer selection
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Modeling evolutionary life history traits of copepods in the Georges Bank and Gulf of Maine region
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作者 Na Li Xianwen Bao +1 位作者 Maochong Shi Meiping Feng 《Acta Oceanologica Sinica》 2025年第8期77-94,共18页
In the paper,copepod universal formulas are applied to construct a copepod individual-based model(IBM),and a genetic algorithm(GA)is incorporated in the formulas with genes as species parameters.The IBM initially cons... In the paper,copepod universal formulas are applied to construct a copepod individual-based model(IBM),and a genetic algorithm(GA)is incorporated in the formulas with genes as species parameters.The IBM initially constructs the individuals with all possible genes similar to the original state of natural selection.Climate-averaged temperature and chlorophyll a(Chl a)time series at the surface layer of fixed points in the Georges Bank(GB)and the Gulf of Maine(GOM)are taken as the model environment.The IBM has been running for 50 a in the environment without inter-annual change.The IBM results indicate that some of the life history traits of the top ten abundant species output by the IBM in the GB and the GOM are consistent with the real species Calanus finmarchicus,Pseudocalanus spp.,Centropages typicus,and Centropages hamatus in terms of reproduction strategy,time to reach the maximum abundance,water temperature preference,and adult body mass.The study of the top ten abundant species with multidimensional scaling(MDS)and clustering analysis(CA)methods indicates that reproduction strategy is the basis for grouping.For the species taking the broadcasting strategy,both GB and GOM environments tend to choose smallbodied species with cold-water preference,such as Pseudocalanus spp.;for the species taking the egg-carrying strategies,the GB environment selects large-bodied species with cold-water preference,such as C.finmarchicus,while the GOM environment selects medium-bodied species with warm-water preference,such as Centropages spp.(C.typicus and C.hamatus).After gene mutation is added to the IBM,the model result gets simple,which needs to be further improved.The significance of the paper lies in systematically studying the impact of GB and GOM environments on the evolutionary life history traits of copepods for the first time. 展开更多
关键词 copepod life history trait individual-based model Georges Bank Gulf of maine
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Characteristics and Main Points of the Theory and Technology of Hypobaric Storage and Preservation of Fresh Agricultural Products: Insights Gained from Two Monographs by Stanley P. Burg
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作者 Xianzhang ZHENG 《Asian Agricultural Research》 2025年第3期27-39,共13页
In 2004 and 2014,two monographs on hypobaric storage(LP)were published by Stanley P.Burg.Based on his theoretical framework and technological advancements,as well as the research and development of equipment conducted... In 2004 and 2014,two monographs on hypobaric storage(LP)were published by Stanley P.Burg.Based on his theoretical framework and technological advancements,as well as the research and development of equipment conducted under his guidance,alongside customer practices and reflections on various scientific literature both domestically and internationally,it is posited that,as articulated in the monograph,misconceptions regarding his theory and technology in Western scientific literature prior to 1985 continue to persist.This ongoing dissemination of misunderstandings has resulted in a near stagnation of research and has adversely impacted the Chinese academic community as well.Consequently,it is essential to delineate the characteristics and main points of its theory and technology,with the aim of offering guidance to individuals seeking to comprehend its foundational purpose.LP technology is a dynamic physical technology that continuously and uninterruptedly extracts air from a closed container and simultaneously introduces fresh,low-pressure moist air from the external environment,while maintaining specific levels of humidity and/or temperature within the container and upholding a predetermined pressure value.Preservation technology is the collective term for the set of various technical parameters associated with preservation,including pressure,relative humidity,and other relevant factors,to which LP equipment is specifically designed.The theory of LP is characterized by the enhanced diffusion of gases and vapors that enter and exit the commodity in a dynamic manner under low pressure conditions.The theoretical points involve equipment performance,low pressure,the impact of trace concentrations of gases such as O_(2),CO_(2) and C_(2)H_(4) that naturally occur at low pressure,diffusive mass transfer,heat transfer,and impacts on the activity of enzymes associated with maturation and senescence.The technology is characterized by dynamic low pressure,and the range of commodities preserved is comparable to that of refrigeration.However,certain commodities exiting the hypobaric environment possess subsequent preservation advantages that are not available through refrigeration.The main points of the technology encompass an extended sotrage life,a postponement of quality degradation,minimized water loss,the suppression of pathogen growth,and the killing of both internal and external insects of the commodity under dynamic low pressure conditions.The core advantage of LP technology lies in its ability to significantly reduce water loss,inhibit respiration and C_(2)H_(4) action,and pathogen growth,killing insects and modulate the activity of enzymes associated with maturation and senescence in post-harvest fresh horticultural products.Consequently,this technology plays a crucial role in prolonging the post-harvest lifespan of these commodities and mitigating quality degradation.Over the past decade,researchers in China have developed a hypobaric short period treatment technology,grounded in LP theory and technical practice,which is commonly referred to as hypobaric treatment.This method has garnered significant attention,leading to an increase in both domestic and international research.A growing body of literature categorizes LP as hypobaric treatment,while some studies also consider vacuum packaging and modified atmosphere packaging(MAP)as LP or hypobaric treatment.Misunderstandings are exacerbated by confusion surrounding nomenclature,which,in conjunction with pre-existing misconceptions,represents a significant barrier to both the research and practical application of the technology.The successful commercial implementation of a vacuum cold fresh chain,centered on LP or hypobaric treatment technology,may be the sole solution to the prevailing misunderstandings associated with LP. 展开更多
关键词 Hypobaric storage Stanley P.Burg Hypobaric treatment preservation THEORY Technology Characteristics and main points Vacuum cold fresh chain
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工艺参数对溢流法水辅助注射成型中纤维堵塞的影响
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作者 余忠 上官元硕 +6 位作者 刘志清 黄益宾 章凯 柳和生 匡唐清 石慧苹 许哲晨 《中国塑料》 北大核心 2026年第2期56-60,共5页
就溢流法水辅注射成型主要工艺参数对短玻纤堵塞水辅制品管道的影响程度进行了探究。结果表明,熔体温度为230~240℃时对该状况的影响显著,如熔体温度由230℃升至240℃时该状况由整个主型腔流道至流道末端一小段;注水延迟时间为3~5 s时... 就溢流法水辅注射成型主要工艺参数对短玻纤堵塞水辅制品管道的影响程度进行了探究。结果表明,熔体温度为230~240℃时对该状况的影响显著,如熔体温度由230℃升至240℃时该状况由整个主型腔流道至流道末端一小段;注水延迟时间为3~5 s时对该状况的影响很大,如注水延迟时间由3 s延迟至5 s时该状况由流道中部一小段至流道的前半段;注水压力为6~8 MPa时对该状况的影响明显,如注水压力由6 MPa增加至8 MPa时该状况由流道的后半区域至流道中部的几小段。 展开更多
关键词 短玻璃纤维 水辅注射成型 堵塞 主型腔
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马骏运用调和致中理念治疗慢性湿疹的临床经验
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作者 张永跟 颜小飞 +3 位作者 郝文哲 胡红昊 张晓梅 李学军 《中华中医药杂志》 北大核心 2026年第1期110-113,共4页
慢性湿疹是临床常见疑难杂病,马骏教授根据慢性湿疹的自身特点用调和致中的理念治疗本病临床疗效显著,总结出慢性湿疹主要病机为湿困脾胃,次要病机为血虚风燥。调和致中、以平为期是本病的治疗大法,其理念源于中医学和法之治,“调”是手... 慢性湿疹是临床常见疑难杂病,马骏教授根据慢性湿疹的自身特点用调和致中的理念治疗本病临床疗效显著,总结出慢性湿疹主要病机为湿困脾胃,次要病机为血虚风燥。调和致中、以平为期是本病的治疗大法,其理念源于中医学和法之治,“调”是手段,“和”是方法,“致中”是结果;主要病机与次要病机并非是一成不变的,甚至在某些情况下可能会发生相互转变,临证时动态关注患者不断变化的状态,应谨守调和致中的理念。 展开更多
关键词 调和致中 慢性湿疹 主要病机 次要病机 马骏 经验
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蒙古主构造线南北地壳变形差异:来自地震各向异性的启示
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作者 强正阳 王娜 吴庆举 《地学前缘》 北大核心 2026年第3期363-374,共12页
蒙古高原位于中亚造山带东部变形核心区域,形成于古生代,并陆续在中生代和新生代时期受到改造,成为研究壳幔变形的理想场所。目前,蒙古高原的地壳变形机制还存在争议,准确的地壳各向异性信息对于理解这一区域地壳变形机制及动力学过程... 蒙古高原位于中亚造山带东部变形核心区域,形成于古生代,并陆续在中生代和新生代时期受到改造,成为研究壳幔变形的理想场所。目前,蒙古高原的地壳变形机制还存在争议,准确的地壳各向异性信息对于理解这一区域地壳变形机制及动力学过程具有重要意义。我们利用远震接收函数重新测量了蒙古中南部地区地壳各向异性参数,最终在39个台站得到了测量结果。Pms到时差变化范围在0.12~0.63 s,平均值为(0.33±0.12)s,在3%各向异性程度以及平均波速3.7 km/s的假设条件下,对应各向异性层厚为(29.60±4.93)km。各向异性快波方向以蒙古主构造线为界,在其北部显示出NW-SE方向,与区域水平主压应力正交,推测是中下地壳成岩矿物受到NE-SW方向的挤压发生晶格定向排列所致。而在蒙古主构造线以南区域,各向异性快波方向则表现为近W-E方向,与块体边界大致平行,推测是块体贴合挤压所产生。此外,断层周边台站表现出与断层走向一致的快波方向,表现出断层对局部各向异性的控制作用。综合对比前人各向异性研究结果,我们认为研究区中、下地壳变形和上地幔是耦合的,但是在蒙古主构造线以南戈壁区域深部可能存在更为复杂的变形机制。 展开更多
关键词 蒙古高原 地壳各向异性 接收函数 Pms震相 蒙古主构造线
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顺北—顺南地区深层碳酸盐岩走滑断裂结构特征及其形成的主控因素分析
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作者 吴孔友 杨言军 +2 位作者 刘寅 洪梅 汪必峰 《浙江大学学报(理学版)》 北大核心 2026年第1期97-108,共12页
塔里木盆地顺北—顺南地区的深层碳酸盐岩走滑断裂发育对下古生界碳酸盐岩具有明显的控藏作用。由于碳酸盐岩岩性脆且致密,走滑断裂水平错动作用必然导致其形成独特的结构特征。针对顺北—顺南地区的深层碳酸盐岩走滑断裂体系,基于现有... 塔里木盆地顺北—顺南地区的深层碳酸盐岩走滑断裂发育对下古生界碳酸盐岩具有明显的控藏作用。由于碳酸盐岩岩性脆且致密,走滑断裂水平错动作用必然导致其形成独特的结构特征。针对顺北—顺南地区的深层碳酸盐岩走滑断裂体系,基于现有研究成果,通过野外相似露头踏勘,结合地震、岩心等资料,利用高精度三维地震数据体走滑断裂精细刻画、地震属性体走滑断裂体系识别、物理模拟实验、应力场数值模拟等技术方法,分析了走滑断裂的结构特征,并对其形成的主控因素进行了归纳总结。研究发现,顺北—顺南地区深层走滑断裂的空间结构主要表现为“平面沿走向分段、剖面分层变形”的特征,在平面上主断裂可划分为张扭段、压扭段、直立段,三者交替出现,在剖面上以中下奥陶统顶界面(T74)为界,将断裂分为深层和浅层系统,深、浅层断裂纵向叠置,分层特征明显。将内部结构划分为“滑动破碎带—诱导裂缝带”二元结构,二者差异明显,特征相异。多期构造活动、应力分布、断裂活动强度、地层岩性和后期的胶结充填作用均可影响断裂带的二元结构。 展开更多
关键词 塔里木盆地 碳酸盐岩 走滑断裂 结构特征 控制因素
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两湖流域主雨季降水年代际变化及其与大气环流的关系
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作者 张剑明 袁靖 +1 位作者 黄晴 姚娟 《热带地理》 北大核心 2026年第3期522-534,共13页
基于1980—2020年两湖流域逐月降水数据,文章揭示了两湖流域主雨季降水的年代际变化特征及其与大气环流的关系。结果表明:两湖流域多年平均主雨季降水量约占全年降水总量的41.4%。在历年观测中,1993年该占比最高,达到49.9%;而1991年则最... 基于1980—2020年两湖流域逐月降水数据,文章揭示了两湖流域主雨季降水的年代际变化特征及其与大气环流的关系。结果表明:两湖流域多年平均主雨季降水量约占全年降水总量的41.4%。在历年观测中,1993年该占比最高,达到49.9%;而1991年则最低,仅为31.3%。从空间分布看,山区丘陵区的主雨季降水量多于平原区。1980—2020年两湖流域主雨季降水呈显著增加的趋势,其中流域中部一带降水有明显增多趋势,而流域西北部和衡邵盆地呈现减少趋势,共经历了偏少(1980—1991年)—偏多(1992—1999年)—偏少(2000—2013年)—偏多(2014—2020年)4个阶段。第一阶段少雨期,欧亚中高纬的大气环流以纬向环流为主,低层风场上中国南方地区为偏南风距平,且为水汽异常辐散区,冷暖气流在黄淮、江淮地区汇合,导致两湖流域降水偏少。第二阶段多雨期,贝加尔湖脊偏强,有利于冷空气南下与南方地区活跃的暖湿气团汇合,对应的水汽场上为水汽异常辐合,两湖流域降水因此偏多。第三阶段少雨期,欧亚中高纬环流较平直,不利于冷空气南下,对应的水汽场上为两湖流域水汽异常辐散区,导致该区域降水偏少。第四阶段多雨期,西风气流上的槽脊系统较强,有利于北方冷空气南下,与两湖流域活跃的暖湿气团汇合,对应的水汽场上为水汽异常辐合,两湖流域降水偏多。 展开更多
关键词 主雨季降水 年代际变化 大气环流 两湖流域
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回溯与展望:新中国成立以来的价值观教育
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作者 王立仁 姜波 《东北师大学报(哲学社会科学版)》 北大核心 2026年第1期98-106,共9页
新中国成立以来的价值观教育发展与社会主义建设伟大实践同频共振。以党和国家中心任务的变化为依据,新中国成立以来的价值观教育发展历史可划分为酝酿和探索阶段、反思和重构阶段、拓展和融通阶段、聚焦和创新阶段。具体表现为价值观... 新中国成立以来的价值观教育发展与社会主义建设伟大实践同频共振。以党和国家中心任务的变化为依据,新中国成立以来的价值观教育发展历史可划分为酝酿和探索阶段、反思和重构阶段、拓展和融通阶段、聚焦和创新阶段。具体表现为价值观教育内容逐渐凝练明确,教育对象从关注重点群体发展到关注全体人民乃至全人类,教育实践从知识教化和理论灌输发展为重视价值观的实践养成。新时代的价值观教育应整体规划价值观教育的基本理念,重点关注青年群体,着力提升社会主义核心价值观自信;在实践推进中聚焦学校主阵地,推动协同育人;既要着眼当前的中国价值观问题,又要放眼世界,关注全人类的共同价值问题。 展开更多
关键词 价值观教育 价值引领 主要特征
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基于主结构提取和AFLBP的织物瑕疵检测方法
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作者 陈梅 金帆 於全豪 《控制工程》 北大核心 2026年第3期551-558,共8页
针对织物瑕疵检测问题,现有的方法大多关注瑕疵特征的提取,而没有考虑如何消除织物自身的纹理结构和织物褶皱等因素对特征提取的干扰,因此,提出一种基于图像主结构提取和自适应快速局部二值模式(adaptive fast local binary pattern, AF... 针对织物瑕疵检测问题,现有的方法大多关注瑕疵特征的提取,而没有考虑如何消除织物自身的纹理结构和织物褶皱等因素对特征提取的干扰,因此,提出一种基于图像主结构提取和自适应快速局部二值模式(adaptive fast local binary pattern, AFLBP)的织物瑕疵检测方法。首先,使用基于总变差模型的纹理图像主结构提取方法,能够去除织物图像中自身纹理信息的干扰;其次,对传统局部二值模式(local binary pattern, LBP)算法进行改进后提出AFLBP算法,用于对图片进行分割获取二值化图像,改善原LBP算法对图像的局部特征进行区分的问题,缓解像素的明显振动变化,在一定程度上提高了图像边缘轮廓提取的准确度;最后,使用支持向量机(support vector machine, SVM)分类器判别分割后的织物二值图像是否含有瑕疵。实验结果表明,所提方法在瑕疵检测的准确度方面表现较好,同时对比其他图像分割算法,所提出的AFLBP算法也有更好的分割效果。 展开更多
关键词 图像分割 主结构提取 AFLBP 织物瑕疵
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基于Copernicus DEM 30的大尺度河道数字高程模型重构方法
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作者 李玉建 赵明成 +2 位作者 李琳 戴文鸿 安鹏 《长江科学院院报》 北大核心 2026年第2期201-210,共10页
为解决在大尺度河道数值模拟中河道遥感影像信息不全和实测地形高程资料部分缺失导致河道数字高程模型难以构建的问题,应用塔里木河阿拉尔—新渠满河段2011年相关水文资料与实测地形高程资料,通过ArcGIS软件结合Google Earth历史影像与C... 为解决在大尺度河道数值模拟中河道遥感影像信息不全和实测地形高程资料部分缺失导致河道数字高程模型难以构建的问题,应用塔里木河阿拉尔—新渠满河段2011年相关水文资料与实测地形高程资料,通过ArcGIS软件结合Google Earth历史影像与Copernicus DEM 30数据绘制河道临水线与外缘线,基于二次插值、平均差值法与局部加权回归算法,结合断面高程数据,完善河道地形高程。通过Mesh Generator组件,重构该河段的河道数字高程模型,并检验数据在MIKE 21水动力-泥沙模块数值模拟中的可行性。结果表明:通过模拟得到的流速、流量-水位关系及河道冲淤变化与实测资料对比,各项指标的误差均符合相关技术规程的允许偏差要求;平均差值法可以弥补主槽与河漫滩高程补衔接不自然的问题;局部加权回归算法能有效平滑河道主槽沿程断面高程数据。研究成果旨在丰富河道地形高程数据的重构方法,为解决大尺度河道DEM难以构建问题提供一种新思路。 展开更多
关键词 大尺度河道 数字高程模型(DEM) Copernicus DEM 30 塔里木河干流
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井研及资阳地区筇竹寺组高长英质页岩形成主控因素研究
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作者 熊亮 相泽厚 +1 位作者 伏美燕 闫亮 《石油实验地质》 北大核心 2026年第1期10-21,共12页
井研及资阳地区下寒武统筇竹寺组是四川盆地重要的页岩气接替层系,其长英质含量高、储层物性较好,但该套高长英质页岩形成的主控因素尚不明确,制约了该层系储层评价与勘探部署。以井研和资阳地区拉长槽中段2口典型钻井为对象,基于扫描... 井研及资阳地区下寒武统筇竹寺组是四川盆地重要的页岩气接替层系,其长英质含量高、储层物性较好,但该套高长英质页岩形成的主控因素尚不明确,制约了该层系储层评价与勘探部署。以井研和资阳地区拉长槽中段2口典型钻井为对象,基于扫描电镜、X射线衍射矿物分析、地球化学元素分析、粒度分析及总有机碳(TOC)含量测定等实验,系统开展了矿物组成特征及长英质含量较高的控制因素研究。研究区筇竹寺组发育在半深水—深水过渡的海槽沉积体系,处于贫氧—缺氧环境(U/Th>0.75),古生产力较高(Ba_(bio)>500μg/g),沉积速率差异较大。从浅水缓坡至深水缓坡,长英质含量由66.7%降至61.4%,TOC含量由0.51%增至2.96%;浅水缓坡(平均>35μm)相较于深水缓坡(平均<30μm)矿物颗粒粒度更粗、分选性更差。研究区筇竹寺组高长英质页岩主要受相对近物源、贫氧—缺氧环境及差异沉积速率控制;浅水缓坡因物源更近、沉积速率较高,矿物颗粒更粗、分选较差。物源距离、氧化还原条件和沉积速率共同控制了高长英质页岩的形成,建立了“高长英质含量下的浅水缓坡低TOC、深水缓坡高TOC”的发育模式。该认识可为四川盆地页岩气储层评价预测及后续勘探开发提供理论支撑。 展开更多
关键词 高长英质页岩 物质组成 主控因素 筇竹寺组 井研及资阳地区 四川盆地
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超大跨悬索桥并置双主缆施工期风致失稳特征试验研究
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作者 李寿英 李林玉 +1 位作者 邓羊晨 陈政清 《土木工程学报》 北大核心 2026年第1期51-60,共10页
悬索桥并置双主缆的缆间间距小,气动干扰效应显著,尤其在无吊索约束的施工阶段,主缆频率低、断面形状不断变化,极易发生大幅有害风致振动。以主跨2180 m的某超大跨径悬索桥的单侧并置双主缆方案为工程背景,设计并制作双主缆施工阶段5种... 悬索桥并置双主缆的缆间间距小,气动干扰效应显著,尤其在无吊索约束的施工阶段,主缆频率低、断面形状不断变化,极易发生大幅有害风致振动。以主跨2180 m的某超大跨径悬索桥的单侧并置双主缆方案为工程背景,设计并制作双主缆施工阶段5种典型截面节段模型,进行多工况下双主缆测振风洞试验,研究单侧并置双主缆在施工期的风致振动特征,并与典型振动工况同参数单主缆风致响应进行对比研究。结果表明:5种典型截面双主缆节段模型均发生大幅度风致振动,最大振幅标准差值高达8.7H;不同风向角和风攻角下双主缆风致振动特征存在明显差异,双主缆施工期风致失稳的可能机理主要包括:主缆自身不稳定外形及缆间气动干扰耦合作用机理、缆间气动干扰单独作用机理、主缆自身不稳定外形单独作用机理;双主缆在架设早期风致失稳问题最为严重,随着双主缆架设的推进,失稳最大振幅呈现减小趋势。 展开更多
关键词 并置双主缆 施工期 风致失稳 气动干扰 风洞试验
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基于改进鲸鱼算法的门式起重机主梁可靠度优化设计
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作者 陈一馨 谭世界 +1 位作者 王玲 刘永生 《湖南大学学报(自然科学版)》 北大核心 2026年第2期66-77,共12页
提出了一种基于改进鲸鱼算法的门式起重机主梁可靠度优化设计方法.通过引入Sine混沌映射、非线性收敛因子及自适应惯性权重以提高基础鲸鱼算法的收敛速度和收敛精度.此外,改进随机概率p以提高全局搜索能力,防止陷入局部最优解.以刚度、... 提出了一种基于改进鲸鱼算法的门式起重机主梁可靠度优化设计方法.通过引入Sine混沌映射、非线性收敛因子及自适应惯性权重以提高基础鲸鱼算法的收敛速度和收敛精度.此外,改进随机概率p以提高全局搜索能力,防止陷入局部最优解.以刚度、强度、稳定性、几何尺寸及设定的可靠度指标为约束条件,建立了门式起重机主梁结构可靠度优化数学模型,分别采用改进的鲸鱼算法、蒙特卡罗模拟可靠度优化方法和结构体系模糊随机可靠度优化方法对主梁进行轻量化设计.研究结果表明,该结构在满足设定约束条件的前提下,采用蒙特卡罗模拟可靠度和结构体系模糊随机可靠度方法优化后的主梁体积分别减少了12.6%和12.33%,轻量化效果显著. 展开更多
关键词 门式起重机主梁 鲸鱼算法 结构体系模糊随机可靠度 优化设计
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2017-2019年宜昌市结直肠癌流行病学特征分析
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作者 范军 丰大利 《云南医药》 2026年第1期38-41,共4页
目的调查宜昌市主城区结直肠癌就诊情况,探讨结直肠癌防治的方式、方法。方法调取宜昌市2017年1月1日-2019年12月31日城区的结直肠癌患者就诊情况,并分析结直肠癌患病的特征、年龄及性别分布情况及变化趋势。结果3年期间的男性、女性的... 目的调查宜昌市主城区结直肠癌就诊情况,探讨结直肠癌防治的方式、方法。方法调取宜昌市2017年1月1日-2019年12月31日城区的结直肠癌患者就诊情况,并分析结直肠癌患病的特征、年龄及性别分布情况及变化趋势。结果3年期间的男性、女性的结直肠癌现患率逐年增高,其中女性增长更快,但结直肠癌现患率男性一直高于女性;现患率的年龄差异明显,3年期间的结直肠癌患者中60岁以上人群的平均现患率是566.67/10万以上且是逐年增加,60岁以下人群的平均现患率只有不到71.09/10万。结论宜昌市结直肠癌现患率逐年上升,60岁以上老年人现患率更高。结直肠癌需要积极防治,老年人群更需重点关注。 展开更多
关键词 主城区 结直肠癌 防治 流行病学
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